Apparatus for raising the disassociation pressure of acetylene in generators



June 1947- J. J. CROWE 2,422,225

APPARATUS: FOR RAISING THE DISASSOCIATION Y PRESSURE 0F ACBTYLBNE IN GENERATORS Filed Jan. 1, 1945 3 Shoots-Sheet 1 I N VEN TOR.

June 17, 1947. CRQWE 1 2,422,225

APPARATUS FOR RAISING THE DISASSOCIATION PRESSURE 0F ACETYLENE IN GENERATORS Filed Jan. 1, 1945 3 Sheets-Sheet 2 1941- J. J. CROWE 2,422,225

APYARATUS FOR RAISING THE DISASSOCIATION PRESSURE OF ACBTYLENB IN GENERATORS Filed-Jan. 1, 1945 3 Sheets-Shoot 3 L Y I mwvmg,

Patented June 17, 1947 52 9 int propane valve'is either open all the way-or closed in Figure 4, the governor has weights 43, each of 'For the purposes of the invention there isprovided in the acetylene discharge pipe I a disc 25 3 having an orifice that produces a pressure viewed from the side, being indicated in Figures. 7 I

' As is well understood in the art, the governor upstream side of the disc 25 is placed in communi-. cation with compartment 22 by means of 'a tube;

21. downstream side of the disc 25 is placed incom- The interior of theracetylene pipe at thetube 28. V I

It will now be seen that the-propane valve l is responsive to the rate ot flow oi acetyle e} through the discharge pipe 'I,"sin ce the greater the flow, the greater will be the pressure drop shaft is. rotated by thevweight motor and controls the speed of rotation of the carbidefeed disc 2 preyiously described in. connection with Figure'l. When the governor shaftlliattains a predetermined speed of rotation, the weights 43 fly out by centrifugal force against the action of coil springs 41 and move brake shoes 43' against 9. disc 48.1 disc is mounted so that it can- V;

municatlon with the endcompartment Z'Lby' 'a- *not'rotateland in standard equipment is fixed against axial movement also, but for the purpose otthe present invention it is mounted for limited on opposite sides of the disc and the greater will be the differential pressure on opposite sides 1- f of the diaphragm l6, and consequently the greater willbe the extent to which the propane valve, is opened to admit propane'tjo thegen'erator. I

In the modification oi the invention shown m; Figure 2,'the valve is also responsive to the flow 'of f sponsive to itsrate of flow as in Figure 1. The,

all the way, and the propane supply is set for an average delivery rate. The propane valveis'in a shown at vIt is'connected't'o a diaphragm 3| 7 which'divides the interior of the housing 29 into acetylene from thegen'erator, but it is not re-, 25

two compartments, one of which, indicatedatfl,

is in communicatlon'with the acetylene discharge pipe I by means of apipe33'. The, other compart-J mentl'indicated'at 34communicates with the interiorof the'generator-by means of a pipe 35, I

Propane is supplied from the cylinder C. to the compartment 34" through a pipe 36, the discharge 1" end of-which isacontrolle'd by the'valve 30. A

coil spring 31 biases the valve toward closed posi tion, 1;. e. toward the 'p'osition'in whichit closes Y the discharge end of the propane pipe' 3li. When acetylene flows from "the i generator through the pipe 'lfthere is-a reduction in pres housing and when such pressure reduction sure in the compartment 32 of thepropane valve reaches a predetermined amount the pressure differential established at opposite sides of the diaphragm opens the valve- 30 to permit the flow of propane front the pipe 38 into the compartf mer t and thence through the pipe into the l acetylene generator. s

In the modification invention shown in Figures 3 and ithe propanesupply is also set for'an, average delivery rate, the propane valve j being either open to permit flow of propane'in'to the generator at the'average rate, or shut to permit no flow at all. The propane valve isshown at 38 (Figure '4). It is positioned in a housing 39 having a propane inletpipe 40 and a propane outlet pipe 4|. Thevalve is biased toward closed position by coil spring 42. The inlet pipe 40 delivers propane from, the cylinder C (Figure 3) to the valve housing 39, but as the valve 38 is normally closed, it preventsintroduction of propane into the generator through the" pipe 4|.

The propane valve '38 is 'operatively connected to the centrifugal governor associated with the 1 motor of the carbide-feed mechanism. As shown located within the above described housing 4 which housesgthefweight motor, the approxi mate position of the shaft, when the housing;- is? axial movement. When the brake shoes'43' are pressedagainstthe disc 48 with sufllcient force, the discis moved axially on the governor shaft 46 (downwardly as'viewed in Figure'4) against the action of a coil spring 49. This axial movement pane valve 3B.v

When acetylene is' withdrawn from the gen: erator and 'causes thefe'ed mechanism tofeed; carbide into the generator ina manner well un--; derstood in the art, thewei'ghts 43. of the centrifugal governor JiviII' be, actuated to maintain i thespeed of operationfof the weight motor sub-.; .stantially constant. ,As} above described;,. the weights 43in moving outwardlyabout their'piv- 0135 44 will move the-disc" axially, and through the lever5l ,willopen the, propanevalve'ali to introduce propane into the generator.- -When withdrawal of acetylene from. the generator is discontinued, or 'is 'reducedrto a very small 7 amount, immediately or soonthereafter :the weight "motor isfautornaticallythrownout of ac tion to discontinue the feed of carbide into thegenerator, as. is;,well understood, iand the centrifugal governorthen allows thepropane valve 38 to'clos'e.

It will now .be seen that inallforms of the invention the propane is introduced into the generator automatically during periods which coincide, at least approximately, with thelperiods when there is v anacetylene der and onthe generator; otherwise, there would b danger of mixingexcess'ive amounts orpropane with the acet ylene and the flame characteristics of torches; supplied with gasfrom the enerator-would be. f adversely affected. 10% of pr'opane is sufllcient for commercial generators to minimize explosion hazard. Preferably, the apparatus functionsto open the propanevalve only when the acetylene demand rises to a certain level.. This is more a desirable in the ,form of apparatus shown in 3 Figures '2 to 4 on which the propane valve is sponse to the rate of flow of acetylene from the generator.

withdrawal of acetylene 'fr0m the generator is In the types of apparatus .shownin Figures fll. .andl 2 the propane valve closes to dis'- ,continue thesupply-of propane to the generator as soon asthe acetylenedemandceases or is reelute 0 a certain lo level,, "Ihisis alsotrue V r of the type of apparatus shownin Figures {and 4 if the carbide ffeedmechamsm and'the cen- J trifugal governor stop functioning as "soon. as. I

discontinued, but ordinarily there is a short lag in the operation of the carbide feed mechanism so that it may continue to function for a brief period of time after the flow of acetylene from the generator ceases. Even so, in this type of apparatus, the propane is supplied to the generatorduring periods which coincide approximately with the periods of acetylene demand.

Any other gas which will sufiiciently reduce the explosion hazard may be introduced into the generator by the apparatus herein described, but propane is preferred because it is inexpensive and widely available. Whatever gas is introduced should, of course, be one that can be used under the operating conditions for which the acetylene is used. If the acetylene is used as a fuel gas to be supplied to cutting and welding torches, the gas introduced may be either propane or any other fuel gas which will raise the disassociation pressure of the acetylene, such as butane or meth-- ane. If the acetylene is used for purposes Where an inert diluent is not objectionable, nitrogen or some other similar inert gas may be'introduced if it has the desired effect of raising the disassociation pressure of the acetylene or reduces the explosion hazard in some other way. When propane is used, the apparatus herein described is preferably designed to control its introduction into the generator in such a way that there is maintained admixed with the acetylene in the generator about of propane, as previously stated, but with some gas other than propane a difierent percentage may be desirable.

I claim:

1. The combination with an acetylene generator having carbide feed mechanism including a motor controlled by a centrifugal governor, of a source of gas to be admitted to the generator, a valve controlling the admission of such gas to the generator, and connections between said governor and the valve whereby the valve is controlled by the rotation of the governor.

2. The combination with an acetylene generator and the means by which acetylene is generated therein, of a source of gas capable when mixed with the acetylene in the generator of reducing the explosion hazard as by raising the disassociation pressure of the acetylene, andmeans in addition to the means for generating acetylene in said generator for automatically admitting gas from said source to the generator during periods which coincide approximately with the periods when there is an acetylene demand on the generator.

3. The combination with an acetylene generator and the means by which acetylene is generated therein, of a source of gas capable when mixed with the acetylene in the generator of reducing the-explosion hazard as by raising the disassociation pressure of the acetylene, and means in addition to the means for generating acetylene in said generator for automatically maintaining in admixture with the acetylene in the generator approximately a predetermined tor and the means by which acetylene is genera ated therein, of a sourceof gas under pressure capable when mixed with the acetylenein the generator of reducing the explosion hazard as by raising the disassociation pressure of the acetylene, piping leading from said source of gas to the interior of the generator, a valve controlling the passage of said gas through the piping to the generator, and means in addition to the means for generating acetylene in the generator operating automatically when acetylene is being withdrawn from the generator to open said valve.

6. The combination with an acetylene generator having means by which acetylene is generated therein and having an acetylene discharge pipe, of a source of gas capable when mixed with the acetylene in the generator of reducing the explosion hazard as by raising ,the disassociation pressure of the acetylene, a valve controlling the admission of such gas to the generator, and means in addition to the means for generating acetylene in the generator responsive to the flow of acetylene through said discharge pipe for con trolling said valve.

'7. The combination with an acetylene generator having means by which acetylene is generated therein and having an acetylene discharge pipe, of a source of gas capable when mixed with the acetylene in the generator of reducing the explosion hazard as by raising the disassociation pressure of the acetylene, a valve controlling the admission of such gas to the generator, and means in addition to the means for generating acetylene in the generator responsive tothe rate of flow of acetylene through said discharge pipe for controlling said valve.

8. The combination with an acetylene generafor generating acetylene in the generator for actuating said valve, said means being in communication with said discharge pipe and responslve to the flow 01 acetylene through it. 1

JOHN J. CROWE.

REFERENCES orrsn The following references are of record in the file of this patent:

UNITED STATES PA'IELN'IS Date Number Name 2,309,701 Kehl Feb. 2, 1943 1,902,757 Boley Mar. 21, 1933 1,573,079 McKee Feb. 16, 1926 1,671,751 Sullivan May 29, 1928 1,096,245 Jenkins May 12, 1914 I FOREIGN PATENIS Number Country Date Great'Britain or 19 03 

